Calix[4]arene-p-sulfonic acid hydrates [CH2(OH)C6H2SO3H]4•nH2O (n = 6, 8, 9, 10, 12): a quantum chemical study

• DOI: 10.1007/s11172-015-1201-2
• Publication Date: 2016-09-26T09:54:36Z
• Authors: T. S. Zyubina; L. V. Shmygleva; R. V. Pisarev; A. S. Zyubin; A. V. Pisareva; Yu. A. Dobrovolsky; V. M. Volokhov
• Keywords: Sulfonic acid; Quantum chemical

The cluster structures of calix[4]arene-p-sulfonic acid hydrates [CH2(OH)C6H2SO3H]4•nH2O (n = 6, 8, 9, 10, 12) and the activation barriers to proton migration in them were studied as functions of the number of water molecules (n) within the framework of the density functional theory using the gradient-corrected methods PBE/PAW and B3LYP/6-31G** in the cluster approximation. The average attachment energy of a water molecule calculated for calix[4]arenep-sulfonic acid polyhydrates is 0.5—0.7 eV, while the calculated activation barriers to proton transfer are close to experimental values (0.2—0.4 eV) and depend on the number of water molecules per SO3H group.